Various methods have been developed to estimate properties of a subterranean formation.
Traditional downhole measurement methods can provide detailed information about formation porosity, fluid saturation distribution through wireline logging such as electric, gamma, neutron logging, nevertheless these methods has limitations on the depth of the investigation of 5-10 cm. Formation testing/sampling tools have deeper radius of the investigation but can provide only averaged information on the formation effective permeability, sample of the reservoir fluid that is representative for the near wellbore zone in general. Sonic/acoustic tools can detect only strong variation in the fluid saturation.
U.S. Pat. No. 7,472,748 describes a method for estimating a property of a subterranean formation wherein a fracturing fluid comprising one or more tracers is introduced into a subterranean formation. A plurality of flowback fluid samples is recovered from the formation and fluid identity data for the fracturing fluid and for one or more of the flowback fluid samples are determined. Then one or more approximate properties of the subterranean formation based on the fluid identity data, one or more subterranean formation properties and at least one reservoir model are determined.
Though known methods are quite useful there is a need for an environmentally friendly high resolution method for estimating properties of a subterranean formation.